BIOS 222 Flashcards
Final Exam
1
Q
A ligand is
A
a thing that binds to a thing
2
Q
Every signaling pathway must have its own unique ligand and receptor
A
false
3
Q
An animal cell receiving no singals
A
is likely to die
4
Q
Gbeta and Ggamma are
A
bound to Galpha in the resting state
5
Q
A dimeric ligand is important for the activation of
A
enzyme coupled receptors
6
Q
A receptor tyrosine kinase
A
can phosphorylate itself
7
Q
In E.S work the 1st messenger that led to his discovery of the 2nd messenger cAMP
A
Epinephrine
8
Q
Treating a cell w/ an antibody against a receptor tyrosine kinase can cause it to form dimers leading to receptor
A
Activation
9
Q
If kinase activity causes a receptor tyrosine kinase to become phosphorylated in the course of activation, then return to the resting state will depend on
A
all of the above
10
Q
M-CDK is most active when its
A
bound to cyclin
11
Q
Wee 1 kinase
A
adds an inhibitory phosphate to M-CDK
12
Q
Molecules that normally put the brakes on the cell cycle are called
A
tumor suppresors
13
Q
Binding of this molecule to its receptor leads to release of Rb block against entry to the cell cycle.
A
mitogen
14
Q
phosphorylation of nuclear lamins is responsible for disassembly of the nuclear envelope at the start of mitosis. The kinase that is responsible is
A
M-CDK
15
Q
After the replication of DNA, sister chromatids are held together by
A
cohesins
16
Q
phosphorylation by wee1 kinase has a ____ effect on the activity of M-CDK
A
-
17
Q
P53 protein is a
A
tumor suppressor
18
Q
Retinoblastoma protein is a
A
Tumor suppressor
19
Q
A licensing factor has this effect on DNA replication
A
limits it to once per cycle
20
Q
Cohesins are agents that link
A
sis chromatids to each other
21
Q
Cohesins are the agents of
A
chromatin condensation
22
Q
DNA damage
A
causes a pause in progress through the cell cycle
23
Q
Force production to segregate chromosomes at mitosis through
A
all of the above
24
Q
kinetochore microtubules
A
get shorter as anaphase proceeds
25
polar microtubules
gets longer as anaphase proceeds
26
At which of the following sites would you expect to see a plus-end-directed kinesin family member that contributes to anaphase chromosome movements
kinetochore microtubule (at - end)
27
p53 is activated in response to DNA damage
by phosphorylation
28
A chromosome can be plucked out of the spindle of a live cell undergoing mitosis. As a result
division will be halted by spindle assembly checkpoint
29
After replication of DNA, sis chromatids are held together by
cohesisn
30
Astral microtubules contributes to
anaphase B chromosome movement
31
A cells karyotype is best observed and evaluated at
metaphase of mitosis
32
An action potential begins w/
the opening of voltage-dependent Na+ channels
33
Astral microtubules are the pop labeled
2 (left side bottom)
34
Almost immediately after opening of Na+ channels in an action potential the membrane is repolarized by the opening of
voltage gated K channels
35
synaptic vesicles are agents of
regulated secretion
36
synaptic vesicles releases their content into
the synaptic cleft
37
a transmembrane protein w/ an extracellular domain that binds to the same domain on a neighboring cell to provide adhesion is considered to be
Homophilic
38
gap junctions
allows small molecules to pass freely btwn 2 connected cells
39
J.G. won the Nobel Prize for his work showing that you can clone a frog...
Adult-skin cell
40
Which of the following are shared by onceogenes and tumor suppressors.
both are found to be mutated at high frequencies in human pop
41
R.C fly avatars are transgenic flies he is using to show that
expressing normal versions of human genes causes cancer in the fly
42
Oncogenes are, simply put mutant forms of
genes that promote cell growth and division in normal cells
43
Which of the following is not pluripotent
Adult skin cell
44
A stem cell that can only give rise to one specific differentiated cell type is considered to be
unipotent
45
Which of the following is not true of induced pluripotent stem (iPS) cells:
require destruction of human embryos to produce them
46
Texas govt... underwent a medical procedure in which he was injected w/ stem cells that came from:
fat tissue removed from his own body
47
A risk that goes w/ intro of embryonic stem cells into the adult human body is
all of the above
48
Retinoblastoma gene defects don't always result in cancer b/c
one copy in Rb patients is defective at birth, the other copy becomes mutated somatically later in life (Sometimes but not always).
49
Viagra impacts signals transduction by
blocking a - regulator of NO signaling
50
Tyrosine kinase receptor activation leads to the appearance of phoshotyrosine residues
at the cytoplasmic domain
51
Small GTP binding proteins like ras and ran are active when they are
bound to GTP
52
Ligand binding outside the cell leads to a change in enzyme activity inside the cell
true in both pathways
53
the 2nd messanger could be cAMP
true in pathway 1
54
The ligand is a dimer
True in pathway 2
55
The receptor has 7 transmembrnae domains
true in pathway 1
56
GTPase activity terminates the activated states of the system
True in pathway 1
57
What gets phosphorylated on tyrosine in response to activation of a receptor t.k
the cytoplasmic domain of the receptor
58
Sound is transduced by the outer hair cells of your inner ear via
mechanically gated ion channels
59
Viagra exerts its effect on signaling by
delaying the end of the activated states of signaling
60
The pathway affected by viagra is
Nitric oxide signaling
61
Ras is an intermediate in
T.k signaling
62
One of the following isn't involved in turning off a pathway for signalling
a G alpha trimeric G protein giving up a GDP and replacing it with a GTP
63
protein kinase A is an effector of
GPCR singaling thru adenylyl cyclase
64
The time it takes to reset an action potential is
in the millisecond range
65
Voltage gated CA ion channels in the presynaptic membrane are responsible for
release of neurotrnasmitter from the presynaptic cells
66
W/out GTP-ran
nuclear-cargo would remain stuck to importin receptors in the nucleus
67
Nuclear targeting of proteins occurs
post-translationally
68
a stop transfer sequence is a signal that
tells a protein crossing the ER membrane that it should exit the...
69
it seems that most of the organelles found in eukaryotic cells are involved in
traffic of materials in and out of the cell by endocytic and exocytic processes
70
W/out signal peptidase, proteins that should be secretes (like antibosies) would
remain tethered to the cell by their signal sequences rather than freely soluble
71
Clathrin is important for
determining which proteins will be included in a newly forming transport vesicle
72
Neurotransmitter gated ion channels
regenerated an action potential in the ost synaptic cells
73
There are a variety of signal sequences that specify where in a cell a given protein belongs... and a mitochondrial localization signal
it would go to the ER
74
There are a variety of signal sequences that specify where in a cell a given protein belongs... expressed in an animal cell?
stay in the cytoplasm
75
There are a variety of signal sequences that specify where in a cell a given protein belongs... nuclear localization signal
directed to ER
76
Glick's studies of golgi traffic in yeast capitalized on the fact that
yeast golgi cisternae aren't stacked like pancakes
77
The cisternal progression model of golgi traffic suggests that
Each cisterna moves thru...
78
Glicks studies employed a green fluorescent early golgi maker...
Green labeled compartments are always green and red are always red
79
In the endocytic pathway empty LDL receptors...
coat proteins like clathrin
80
The cisternal progression model for Golgi transport is analogous to an
automobile assembly line except that
Car stands still and different teams of workers are bussed in to complete
tasks
81
When George Palade carried out his pulse label experiment with rabbit salivary
glands which synthesize mostly amylase, he saw that after different chase times
all of the above
82
What Palade saw in his pulse chase experiments was sequential labeling of
The ER and then the Golgi and then the secretory granules
83
. If instead of the pulse chase Palade had left the radioactive material incubating
for an hour and then examined it he would have seen that
All of the compartments he described were labeled
84
Given what you know about George Palade’s pulse chase experiments and what
you know about receptor-mediated endocytosis, if you added LDL with
radioactive cholesterol to cells in culture you would probably see that
radioactivity
At early time points radioactivity appears in coated vesicles and
endosomes and later on appears in lysosomes
85
Entry of proteins to the mitochondrion depends on
Post translational entry of complete proteins into organelle
86
The chromosome movements of anaphase A of mitosis are based on
Shortening of population 2
